[Eosinophilic cation protein and development of restenosis of drug covered stents]

Aim of the study was to assess activation of eosinophils as well as allergic and inflammatory reactions of the body in development of restenosis after implantation of stents with drug covering. We included into the study 32 patients with ischemic heart disease (IHD) and stable angina subjected to repeat coronary angiography during first year after endovascular myocardial revascularization with the help of stents with drug covering, and 11 healthy persons. Levels of eosinophilic cation protein (ECP), immunoglobulin E (IgE), and C-reactive protein (CRP) in blood plasma of patients and healthy persons was determined by immunoenzyme assay. According to results of angiographic study patients were divided into 2 groups: the first comprised 19 patients in whom no instent restenosis was found, the second comprised 13 patients in whom formation of restenosis at least in one stent was noted. Patients in these groups did not differ by age, sex, smokers and nonsmokers ratio, presence of hyperlipidemia, and angiographical characteristics of involved arteries. In patients with restenosis of stents blood plasma ECP level was 17.7 (11.2-24.0) g/ml and significantly higher than in patients without restenosis [9.0 (6.4-12.9) g/ml; p=0.017]. Blood level of IgE in these groups of patients did not differ [58.8 (42.1-164.0) and 52.9 (12.8-76.1) mg/ml, respectively; p=0.40] and did not differ from IgE level in blood of healthy volunteers [32.0 (21.2-80.8) mg/ml; p=0.91]. CRP level in patients with IHD was higher than in healthy volunteers [0.36 (0.1-0.75) mg/ml; p=0.0008)], but did not differ significantly in groups of patients with and without restenosis [2.38 (0.30-4.08) and 1.63 (0.61-2.47) mg/ml, respectively; p=0.52]. It was found that in the group of patients with low blood level of ECP (<11 g/ml) restenoses were revealed in 19% while in the group with higher blood level of ECP (>11 g/ml) - in 62% of cases (p=0,019). In patients subjected to coronary stenting with higher level of ECP in blood we noted more frequent development of restenoses than in patients with low level of this protein. The data obtained allow to suggest presence of relationship between development of restenosis and elevated activity of eosinophilic granulocytes in patients with IHD after revascularization.